Writing pen



FIG. 1 is a perspective view of a writing pen according to my design;

FIG. 2 is a right side elevational view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a rear elevational view thereof;

FIG. 6 is a top view thereof taken from the orientation of the writing pen shown in FIG. 2; and,

FIG. 7 is a bottom view thereof taken from the orientation of the writing pen shown in FIG. 3. 

The ornamental design for writing pen, as shown and described. 